BERGHIA CREUTZBERGI MARCUS & MARCUS, 1970

Material examined: Praia de Armação (Buzios, Rio de Janeiro), 1 July 1999, one specimen, 0-m depth, 13-mm long.

External morphology: The animal is thin and elongated. The body colour is brown with whitish spots on the dorsum and cerata (Fig. 1E). Oral tentacles are elongate with translucent brown bases and whitish pigment on the apical portion. The brown rhinophores bear papillae. In the preserved state, a narrow longitudinal fold on the anterior face is present in each rhinophore. The bases of the rhinophores are very close, and have a white spot on the head below them. The cerata are organized in five pairs of horseshoeshaped arches (Fig. 5A). The first group contains the largest number of cerata (about 14). The second arch contains ten cerata, and the number diminishes toward the posterior end. The cerata of the posterior groups are stouter than the anterior ones, and have pointed tips. The genital opening is located on the right side, in front of the first arch of cerata. The anus is situated inside the second arch. The whitish foot ends in a thin and translucent tail.

Internal morphology: The radular formula is 18 ¥ 0. 1. 0. The arched teeth posses numerous denticles (Fig. 5B). One large tooth has 35 denticles on each side. The central denticle is smaller, and on its sides larger and a smaller denticles are arranged alternately (Fig. 3E). The jaws are each 820-Mm long, and are nearly transparent–yellowish. The masticatory border is smooth (Fig. 3F).

Remarks: Our specimen coincides with that described by Marcus & Marcus (1970), in coloration, ceratal arrangement, and radula.

The species Millereolidia ritmica (Ortea, Caballer & Espinosa, 2003) from Costa Rica has similar teeth to those of B. creutzbergi, with alternating large and small denticles. Both species have brown body colour with whitish spots on the dorsum, the rhinophores bear papillae, and most of the cerata are organized in five pairs of horseshoe-shape arches. However M. ritmica differs from B. creutzbergi: it has an extremely thin and long tail, the papillae of the rhinophores are arranged in rings, the first ceratal group forms a triangle, and the masticatory border is denticulate.

Distribution: Curaçao (Marcus & Marcus, 1970); Barbados (Edmunds & Just, 1983); Cayman Island (Hess et al., 1994); Bahamas (Redfern, 2001).

Brazil: This is the first record of this species from Brazil (Praia de Armação, Buzios, Rio de Janeiro).